{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4073-2BB34","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4073-2BB34","canonicalUrl":"https://aoctrl.com/siemens/3RW4073-2BB34","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4073-2BB34","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4073-2BB34 soft starter, S12 frame size, 230 A at 40 °C, 50/60 Hz, 600 V insulation class, with motor overload protection and adjustable current limitation.","salesMarkdown":"## 230 A continuous — the thermal ceiling that governs the motor The 3RW4073-2BB34: That 230 A is the continuous current the thyristor stack can carry without exceeding the junction temperature limit — it sets the maximum motor FLA this unit can start and run across. Built-in motor overload protection and intrinsic device protection mean the soft starter handles both the motor thermal model and its own heatsink monitoring — no separate overload relay needed in most installations. The adjustable current limitation lets you cap the start current below the full-voltage locked-rotor draw, which is the whole point of a soft starter on a conveyor or pump. Frame size S12 tells the panel builder the busbar pattern and the mounting hole layout. The unit is screw-fixed to a vertical surface; without the add-on fan the tilt tolerance is tight (±10°), so the panel backplate needs to be reasonably plumb. With the fan you get ±90° rotation and ±22.5° tilt front-to-back. ## Wiring and integration — main circuit is busbar, control is screw-clamp The main circuit connection is via busbar — no cable lugs on the thyristor poles. The busbar cross-section range is 70–240 mm² stranded or 50–240 mm² finely stranded, with an alternative kcmil range of 2/0–500 kcmil for the main contacts. The back clamping point accepts 250–500 kcmil; the front point takes 3/0–600 kcmil. If you're using both clamping points, the minimum is 2x 2/0 and the maximum is 2x 500 kcmil. The maximum motor cable length is 300 m, which covers most in-plant runs but may be marginal for long-distance well-pump installations. Pollution degree 3 per IEC 60947-4-2 means the creepage distances are designed for conductive pollution environments — typical in industrial panels where dust and humidity combine. The 600 V insulation voltage rating covers 480 V and 600 V nominal systems with margin. ## Active production — standard BOM line, not a legacy hunt The SIRIUS family is Siemens' mainstream soft starter platform, so spare parts, documentation, and SITOP power supply compatibility are all current. The unit is not an inside-delta configuration — it's a standard in-line soft starter, which is the common topology for most pump and fan applications.","metaTitle":"Siemens 3RW4073-2BB34 SIRIUS Soft Starter, 230 A, S12 Frame","metaDescription":"Siemens 3RW4073-2BB34 SIRIUS soft starter, 230 A at 40 °C, S12 frame, active production. Motor overload protection, adjustable current limit, 50/60 Hz.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Soft Starters"],"specifications":{"Depth":"278mm","Solid":"2x (0.25 ... 1.5 mm²)","Width":"160mm","title":"3RW4073-2BB34","Height":"230mm","Upwards":"100mm","Stranded":"70 ... 240 mm²","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter S12 205 A, 150 hp/460 V, 50 °C 200-460 V AC, 115 V AC spring-type terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5073-2AB14<<","During Storage":"-40 ... +80°C","External Reset":"Yes","Finely Stranded":"50 ... 240 mm²","lifecycle_stage":"current","During Operation":"-25 ... +60°C","Fastening Method":"screw fixing","Minimum Load [%]":"20%","For Main Contacts":"2/0 ... 500 kcmil","Mounting Position":"With additional fan: With vertical mounting surface +/-90° rotatable, with vertical mounting surface +/- 22.5° tiltable to the front and back Without additional fan: With vertical mounting surface +/-10° rotatable, with vertical mounting surface +/- 10° t","Product Brand Name":"SIRIUS","Degree Of Pollution":"3, acc. to IEC 60947-4-2","Product Designation":"Soft starter","Wire Length Maximum":"300m","Derating Temperature":"40°C","Inside-Delta Circuit":"No","at 50 Hz rated value":"115V","at 60 Hz rated value":"115V","at 40 °C rated value":"230A","at 50 °C rated value":"205A","at 60 °C rated value":"180A","For Auxiliary Contacts":"2x (24 ... 16)","For Main Current Circuit":"busbar connection","Motor Overload Protection":"Yes","Using Both Clamping Points":"min. 2x 2/0, max. 2x 500 kcmil","Intrinsic Device Protection":"Yes","Adjustable Current Limitation":"Yes","Size Of Engine Control Device":"S12","Using The Back Clamping Point":"250 ... 500 kcmil","Insulation Voltage Rated Value":"600V","Using The Front Clamping Point":"3/0 ... 600 kcmil","Operating Frequency Rated Value":"50 ... 60Hz","Display Version For Fault Signal":"red","Integrated Bypass Contact System":"Yes","For Auxiliary And Control Circuit":"spring-loaded terminals","Product Component Motor Brake Output":"No","during storage according to IEC 60721":"1K6 (only occasional condensation), 1C2 (no salt mist), 1S2 (sand must not get inside the devices), 1M4","reference code according to EN 61346-2":"Q","during operation according to IEC 60721":"3K6 (no formation of ice, no condensation), 3C3 (no salt mist), 3S2 (sand must not get into the devices), 3M6","during transport according to IEC 60721":"2K2, 2C1, 2S1, 2M2 (max. fall height 0.3 m)","Finely Stranded With Core End Processing":"2x (0.25 ... 1.5 mm²)","Number Of Poles For Main Current Circuit":"3","Evaluation Of Thermistor Motor Protection":"No","at standard circuit at 40 °C rated value":"132kW","at standard circuit at 50 °C rated value":"150hp","Finely Stranded Without Core End Processing":"min. 2x 50 mm², max. 2x 185 mm²","number of CO contacts for auxiliary contacts":"1","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"2","Type Of Voltage Of The Control Supply Voltage":"AC","Control Supply Voltage Frequency 1 Rated Value":"50Hz","Control Supply Voltage Frequency 2 Rated Value":"60Hz","Installation Altitude At Height Above Sea Level":"5 000m","continuous operating current [% of Ie] at 40 °C":"115%","Operating Voltage At Standard Circuit Rated Value":"200 ... 460V","contact rating of auxiliary contacts according to UL":"B300 / R300","Relative Negative Tolerance Of The Operating Frequency":"-10%","Relative Positive Tolerance Of The Operating Frequency":"10%","Relative Negative Tolerance Of The Control Supply Voltage Frequency":"-10%","Relative Positive Tolerance Of The Control Supply Voltage Frequency":"10%","Relative Negative Tolerance Of The Operating Voltage At Standard Circuit":"-15%","Relative Positive Tolerance Of The Operating Voltage At Standard Circuit":"10%","power loss [W] at operational current at 40 °C during operation typical":"90W","relative negative tolerance of the control supply voltage at AC at 50 Hz":"-15%","relative negative tolerance of the control supply voltage at AC at 60 Hz":"-15%","relative positive tolerance of the control supply voltage at AC at 50 Hz":"10%","relative positive tolerance of the control supply voltage at AC at 60 Hz":"10%","Adjustable Motor Current For Motor Overload Protection Minimum Rated Value":"80A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/767751c2eaec6644fc53050f298c34e0.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=12712&mlfb=3RW4073-2BB34"},"ai":{"faq":[{"question":"What is the continuous current rating of the 3RW4073-2BB34 at elevated ambient temperatures?","answer":"The unit is rated 230 A at 40 °C, derating to 205 A at 50 °C and 180 A at 60 °C. The 40 °C figure is the thermal ceiling; above that you need to account for the derating curve in your panel thermal design."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4073-2BB34","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3RW4073-2BB34 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}